div {
    width: 150px;
    height: 150px;
    border: solid 5px red;
    display: inline-block;
    margin-left: 20px;
}
.one {
    background-image: url(../img/bgimage1.jpg);
}
.two {
    background-image: url(../img/bgimage-2.jpg);
}
.three {
    background-image: url(../img/bgimage-3.jpg);
}
.four {
    background-image: url(../img/bgimage-4.jpg);
}
.one,
.two,
.three,
.four {
    background-size: cover;
}